Question

tìm x: 

1) 3/x-5 = -4/x+2

2) x+3/-4 = -9/x+3

3) ( 3 4/5-2x ) . 1 1/3 = 5 5/7

GIÚP MÌNH VỚI

Answer 1

\(\frac{3}{x-5}=-\frac{4}{x+2}\)

=> 3 ( x + 2 ) = 4 ( x - 5 ) 

=> 3x + 6 = 4x - 20

=> 3x - 4x = - 6 - 20

=> - 1x = - 26

=> x = 26

Answer 2

1) 3/x-5=-4/x+2

     3x+6=-4x+20

     7x .  =14

      x  .   =2

2) x+3/-4=-9/x+3

   (x+3)^2=36

  Ta có hai trường hợp:

*x+3=6=)x=3

*x+3=-6=)x=-9

Answer 3

3) (34/5-2x). 11/3=55/7

     34/5-2x .          =15/7

      75-30x.            =238

           30x.            = -163

               x.            =-163/30

Answer 4

\(\frac{3}{x-5}=\frac{-4}{x+2}\)

\(\Rightarrow3x+6=-4x+20\)

\(\Rightarrow3x+4x=20-6\)

\(\Rightarrow7x=14\)

\(\Rightarrow x=2\)